(1) Field of the Invention
The present invention relates to a digital broadcast receiving apparatus, a semiconductor integrated circuit, and a digital broadcast receiving method, and relates particularly to a digital broadcast receiving apparatus which receives a digital broadcast radio wave including a first digital broadcast and a second digital broadcast that are compressed, and which outputs the video data of the first digital broadcast or the second digital broadcast.
(2) Description of the Related Art
In digital terrestrial television broadcasting, a full-segment broadcast (hereinafter, Full Seg) for stationary apparatuses and a one-segment broadcast (hereinafter, One Seg) for portable apparatuses and mobile objects are simultaneously on air in plural segments in each channel. In other words, an identical content is simultaneously broadcast in plural segments in each channel.
As a digital broadcast receiving apparatus to be equipped on portable apparatuses and mobile objects, such as a car navigation system and an in-vehicle television, a digital broadcast receiving apparatus is suggested which receives Full Seg and One Seg and automatically determines the segment to be watched according to the receiving status of digital broadcast signals, the decompression status of the digital data, and other various conditions.
Specifically, the digital broadcast receiving apparatus selects high-definition Full Seg as a target broadcast when the receiving status is good, and selects One Seg which is lower-definition but easier to receive as the target broadcast when the receiving status is poor.
For example, a digital broadcast receiving apparatus described in Patent Reference 1 (Japanese Unexamined Patent Application Publication No. 2007-49460) is known as the digital broadcast receiving apparatus which automatically switches the target broadcast.
In addition, for the digital broadcast receiving apparatus described in Patent Reference 1, it is possible to reduce discomfort that is felt by a viewer when the target broadcast is switched, by decoding a frame having an earlier timing of display with delay, along with the decoding of a frame having a later timing of display.
Such adjustment of the frame having an earlier timing of display to the frame having a later timing, however, causes a lag in the display of the frame having an earlier timing of display behind the time at which it should actually be displayed.
For example, this causes a clock display or the like in the video to indicate the time behind the actual time.
In addition, it is preferable that the digital broadcast receiving apparatus which automatically switches the target broadcast should further reduce the amount of time required for switching the target broadcast. Specifically, the discomfort felt by the viewer at the moment of switching can be reduced through reduction of the time during which no picture is displayed.